Question

If x – y = 8 and x2 + y2 = 144, the value of xy is ____

Answer 1

Step-by-step explanation:

Correct option is A)

Given that: x+y=12 and xy = 32

Using the identity, (x+y)

2 = x 2

+2xy+y ⇒ (12)

2=x 2

+64+y ⇒ 144 = x

2+y 2+64

⇒ 144−64 = x

2+y 2

⇒ 80 = x

2 +y 2

The answer is x

2+y 2= 80